This invention pertains to a system for separating particulate solids and condensable vapors from a gas stream. It pertains particularly to such a system which utilizes a cyclone separator, gas cooler and solids filter such that the coarser particulate solids are removed in the separator upstream of the gas cooler and are collected in a filter vessel together with filtered finer solids mixture to promote uniform withdrawal of the solids from the filter vessel.
Many devices and methods have been developed for separation of fine particulate solid materials from gases, such as from hot combustion gases containing such particles. For example, U.S. Pat. No. 2,400,645 to Huff discloses a system for separating catalyst particles from gases containing such particles by utilizing a cyclone separator from which cleaned overhead gas is passed upwardly through a filtering zone formed by a bed of larger and smaller particles arranged in series. U.S. Pat. No. 4,110,088 to Cold et al discloses apparatus for removing water-soluble pollutants and particles from flue gases by utilizing a gas solids separator having a spray chamber located upstream of a cyclone separator and a downstream distillation tower. U.S. Pat. No. 4,750,916 to Svensson discloses a gas-solids separator device utilizing precooling and aftercooling steps before and after filtration and electrostatic precipitation steps. U.S. Pat. No. 4,865,629 to Zievers et al discloses a process for filtering fine particles from a hot gas stream by utilizing two cyclone separators located upstream of a filter. Also, U.S. Pat. No. 5,215,553 to Herman et al discloses a two-stage mechanical separator having a concentric swirl section provided upstream of a cyclone separator. Although these known gas-solids separation devices have been found useful, they have various disadvantages so that further improvements in separation of particulate solids and condensable liquid fractions from hot feed gases is desired.